Coated-fine-aggregate, concrete composition and method

• US 9,783,457 B2
• Filed: 05/31/2016
• Issued: 10/10/2017
• Est. Priority Date: 07/01/2014
• Status: Active Grant

• Current Assignee: AquaSmart Enterprises, LLC
• Original Assignee: AquaSmart Enterprises, LLC
• Inventors: Hendrickson, Calder
• Primary Examiner(s): CHIN, HUI H
• Application Number:
  US15/168,821
• Publication Number:
  US 20160272543A1
• Time in Patent Office: 497 Days
• Field of Search: 524 4
• CPC Class Codes: B01J 20/262 obtained otherwise than by reactions only involving carbon to carbon unsaturated bonds, e.g. obtained by polycondensation macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds per se C08G
• CPC Class Codes: B28B 1/14 by simple casting, the material being neither forcibly fed nor positively compacted for molten material B28B1/54
• CPC Class Codes: B28B 17/02 Conditioning the material prior to shaping for mixtures containing clay or cement B28C
• CPC Class Codes: C04B 14/06 Quartz; Sand
• CPC Class Codes: C04B 16/04 Macromolecular compounds C04B16/02 takes precedence
• CPC Class Codes: C04B 20/1033 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C04B 2103/0051 Water-absorbing polymers, hydrophilic polymers
• CPC Class Codes: C04B 24/287 Polyamides
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 28/14 containing calcium sulfate cements gypsum-paper plates E04C
• CPC Class Codes: C04B 40/0633 Chemical separation of ingredients, e.g. slowly soluble activator
• CPC Class Codes: E04G 21/02 Conveying or working-up concrete or similar masses able to be heaped or cast in connection with finishing work E04F; construction and surfacing of floorings made of similar material to roads or pavements E01C; in connection with barrages E02B7/00; in connection with foundations E02D15/00; composition of concrete C04B; working concrete in general, e.g. mixing machines B28C

Abstract

A concrete composition and method include a portion of fine aggregate bearing a coating of a polymer, which may be a continuous coating layer or a layer of powdered, discrete particles embedded in a binder. The polymeric coating may be a super absorbent polymer (insoluble in water, but absorbing water), or another polymer such as the acrylamides, co-polymers thereof, polyacrylamides, or the like (soluble in water). The coating absorbs water, but particles are too small to form significant voids. Water is absorbed into the concrete mix in far greater proportions (e.g. w/c ratio over 0.5) improving workability, doubling workability time, and improving ultimate compressive stress (strength).

Claims

1. A composition comprising:

coarse aggregate comprising rocks of a comparatively larger size;

fine aggregate comprising granules of sand having an average maximum dimension substantially smaller than the coarse aggregate;

cement; and

polymer coated aggregate comprising a portion of the fine aggregate having the granules individually powder coated with a powder comprising a water-absorbing polymer.

2. The composition of claim 1, wherein the polymer coated aggregate constitutes less than about one tenth of the fine aggregate.

3. The composition of claim 2, wherein the powder is bound by a binder to the granules individually, as a substrate.

4. The composition of claim 1, wherein the polymer coated aggregate further comprises a shell.

5. The composition of claim 1, wherein the powder is comprised of at least two polymers selected from an acrylamide, an acrylamide co-polymer, a polyacrylamide (PAM), and a super absorbent polymer (SAP).

6. The composition of claim 5 further comprising a binder binding the contact portions of the powder to the substrate.

7. The composition of claim 1, constituted from parts proportioned by weight, wherein:

the cement constitutes an amount of from about one and a half to about two and a half parts;

the fine aggregate constitutes from about 3 to about 5 parts;

the coarse aggregate constitutes from about 3 to about 5 parts; and

the water constitutes from about 1.25 to about 2 parts.

8. A method of combining constituents, the method comprising:

selecting a coarse aggregate comprising rocks of a comparatively larger size;

selecting a fine aggregate comprising granules of sand substantially smaller than the rocks;

selecting a cement;

selecting a polymer comprising a powder having particles, dry, discrete, and comminuted to a size smaller than the granules; and

coating, by powder coating, a portion of the fine aggregate with the polymer in a manner that maintains the portion as individual granules.

9. The method of claim 8, further comprising:

coating, by powder coating, the portion of the fine aggregate with a second polymer comprising a powder having particles, dry, discrete and comminuted to a size smaller than the granules.

10. The method of claim 8, further comprising:

coating the portion of the fine aggregate with a shell.

11. The method of claim 8, further comprising:

mixing the constituents with water such that the cement and the fine aggregate effectively completely fill interstitial space between the rocks of the large aggregate; and

casting the mixture into a restraint effective to mold the mixture to a shape.

12. The method of claim 11, further comprising:

providing, by the coating, water into the cement effective to maintain fluidity of the mixture for a period greater than one and a half hours; and

curing the constituents to a level of compressive strength undiminished by the water.

13. The method of claim 8, wherein the polymer is selected from polyacrylamide, a co-polymer of at least one of an acrylate, acrylic, and acrylamide, an acrylamide compound, and a super absorbent polymer.

14. A method of providing a polymer-coated fine aggregate, the method comprising:

selecting a fine aggregate comprising granules having an average effective diameter effectively equivalent to an average effective diameter of sand;

selecting a polymer comprising a powder having particles, dry, discrete, and comminuted to a size smaller than the granules; and

coating, by powder coating, the fine aggregate with the polymer in a manner that maintains the fine aggregate as individual granules.

15. The method of claim 14, wherein the polymer is selected from polyacrylamide, a co-polymer of at least one of an acrylate, acrylic, and acrylamide, an acrylamide compound, and a super absorbent polymer.

16. The method of claim 14, further comprising:

washing the fine aggregate after selecting the fine aggregate.

17. The method of claim 14, further comprising:

coating the fine aggregate with a shell.

18. The method of claim 16, further comprising:

coating, by powder coating, the fine aggregate with a second polymer comprising a powder having particles, dry, discrete, and comminuted to a size smaller than the granules in a manner that maintains the fine aggregate as individual granules.

19. The method of claim 14, further comprising:

washing the fine aggregate after selecting the fine aggregate; and

applying a binder to the fine aggregate before coating the fine aggregate with the polymer.

20. The method of claim 14, further comprising:

curing the fine aggregate after coating the fine aggregate with the polymer.